Users Guide

Calculation For Maximum Virtual Disk Size
The Create Virtual Disk Express Wizard displays the minimum and maximum values for the virtual disk size. This section describes how
the maximum possible size for the virtual disk is calculated based on the controller type. To identify the controller type, see RAID
Controller Technology: SATA and SAS.
SATA RAID Controllers
When using a SATA RAID controller, the controller calculates the maximum virtual disk size based on your RAID level selection and the
available physical disk space provided by all suitable physical disks attached to the controller. For example, if the controller contains 12
physical disks with available space and you have specified a RAID 5, then the controller calculates the maximum virtual disk size based on
the disk space provided by the 12 physical disks, because the 12 physical disks can be included in a RAID 5.
NOTE: SATA RAID does not support disks from MX5016s.
SAS RAID Controllers
When using a SAS controller, the controller calculates the maximum virtual disk size based on the available disk space provided by the
minimum number of physical disks required to create the RAID level you selected. For example, if you specified a RAID 5, then the
controller calculates the maximum virtual disk size based on three physical disks, because only three physical disks are required to create a
RAID 5.
Channel-Redundant Virtual Disks
When creating a virtual disk, it is possible to use disks attached to different channels to implement channel redundancy. This configuration
might be used for disks that reside in enclosures subject to thermal shutdown.
NOTE:
Channel redundancy only applies to controllers that have more than one channel and that attach to an external
disk enclosure.
Creating Virtual Disks
Does my controller support this feature? See Supported Features.
WARNING:
There is an automatic initialization in the background which starts and if there are some user data it will be
erased.
In order to implement RAID functions, you must create a virtual disk. A virtual disk refers to storage created by a RAID controller from one
or more physical disks. Although a virtual disk may be created from several physical disks, it is seen by the operating system as a single
disk.
Before creating a virtual disk, you should be familiar with the information in Considerations Before Creating Virtual Disks.
Storage Management provides wizards to help you create a virtual disk:
• The Create Virtual Disk Express Wizard calculates an appropriate virtual disk layout based on the available space and controller
considerations. Using this wizard, you can quickly create a virtual disk using recommended selections.
• The Create Virtual Disk Advanced Wizard allows you to specify the read, write, and cache policy for the virtual disk. You can also
select the physical disks and the controller connector to be used. You need a good knowledge of RAID levels and hardware to use the
advanced wizard.
Reconfiguring Or Migrating Virtual Disks
Does my controller support this feature? See Supported Features.
Reconfiguring or migrating a virtual disk enables you to increase the capacity or change the RAID level of the virtual disk.
NOTE:
On software RAID S110 and S130 controllers, if a physical disk (SATA SSD or HDD) is removed from a virtual disk
and the same physical disk is reinserted (hot plug) into the virtual disk instantly, within a fraction of a second, then the
virtual disk state is displayed as Ready and the physical disk state is displayed as Online. However, if the same physical
disk is reinserted after a short delay, then the virtual disk state is displayed as Degraded and the physical disk state is
displayed as Ready.
114 Virtual Disks